In the process of making paper, water has to be extracted from the pulp, and so the pulp is laid over a large screen, called wire. Paper-making wires used for pulp-dewatering consist of multiple layers of a woven fabric made of synthetic resin fibers. Such wires can become accidentally perforated during use. A perforated fabric causes defects in the paper and the wire must be replaced or repaired. Such wires are very expensive, costing over one hundred thousand dollars. Replacing a damaged wire can take many hours, causing downtime of the paper-making machine. It has therefore been tried, but without success to repair perforations with patches. There are, however, many disadvantages to using patches. For example, repairs involving chemical adhesives, do not last as the patches fall off because of the speed at which the wires move (vibration, centrifugal force, etc). Sewing and stapling repair methods offer better resistance to mechanical wear, but do so at the expense of protrusions which introduce undesirable turbulences on the pulp-contacting wire surface, which results in defects in the paper being made.
Resistance to mechanical and chemical wear as well as evenness of the patch surface is therefore highly desirable. Ability to repair the wire without removing the wire from the paper-making machine is also highly desirable in order to minimize downtime and associated financial losses.